*,
body {
    margin: 0;
    padding: 0;
    outline: none;
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}
/* 水平居中 */
.justify-content-center {
    display: flex;
    justify-content: center;
}
/* 自动换行 */
.flex-wrap{
    display: flex;
    flex-wrap: wrap;
}
/* 水平双向对齐 */
.justify-content-space-between {
    display: flex;
    justify-content: space-between;
}
/* 垂直居中 */
.align-items-center{
    display: flex;
    align-items: center;
}
/* 垂直下端对齐 */
.align-items-end{
    display: flex;
    align-items: flex-end;
}
/* 水平左端对齐 */
.justify-content-start{
    display: flex;
    justify-content: start;
}
/* 水平右端对齐 */
.justify-content-end{
    display: flex;
    justify-content: end;
}
/* 垂直向上对齐 */
.align-items-start{
    display: flex;
    align-items: flex-start;
}
.top {
    background-image: url("../img/jghy.jpg");
    background-size: 1000px calc(1000 *1287px/1920);
    width: 1000px;
    height: 500px;
}

.top>div>div {
    width: 800px;
    color: white;
}

.top>:nth-child(1) {
    background-color: rgb(51, 51, 51);
}

.logo {
    height: 50px;
    display: flex;
    align-items: end;
}

.logo>div>img ,.img{
    height: 40px;
}

.logo>:nth-child(2)>:nth-child(1) {
    font-size: 18px;
}

.logo>:nth-child(2)>:nth-child(2) {
    font-size: 12px;
}

.nav>div {
    padding: 0 15px;
    line-height: 50px;
}

.nav>div:hover {
    background-color: rgb(215, 41, 42);
    cursor: pointer;
}

.top>:nth-child(2) {
    width: 100%;
    height: 450px;
}
.top>:nth-child(2)>div{
    width: 80%;
    height: 450px;
}
.foot>div{
    width: 1000px;
    height: 20px;
    background-color: rgb(51, 51, 51);
}

/* 除主页外的头部 */
.top-two {
    background-image: url("../img/scott-webb-22437.jpg");
    background-size: 1000px calc(1000 *1287px/1920);
    width: 1000px;
    height: 500px;
}

.top-two>div>div {
    width: 800px;
    color: white;
}

.top-two>:nth-child(1) {
    background-color: rgb(51, 51, 51);
}
.top-two>:nth-child(2) {
    width: 100%;
    height: 450px;
}
.top-two>:nth-child(2)>div{
    width: 80%;
    height: 450px;
}
.box{
    transition: all .6s;
    cursor: pointer;
}
.box:hover{
    transform: translateY(-3px);
    background-color: #f3f3f3;
    box-shadow: -5px 5px 10px #cecece;
    color: #e02a26;
}
